JP2007182984A

JP2007182984A - Tapping screw

Info

Publication number: JP2007182984A
Application number: JP2006098756A
Authority: JP
Inventors: Tokihiro Shuyama; 祝浩朱山; Hidetaka Fujita; 英貴藤田
Original assignee: KAMIYAMA TEKKOSHO KK; Muro Corp
Current assignee: KAMIYAMA TEKKOSHO KK; Muro Corp
Priority date: 2005-12-09
Filing date: 2006-03-31
Publication date: 2007-07-19

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tapping screw capable of preventing infiltration of water from an external part, particularly, infiltration of the water to the head part side from the tip part side of a screw part when fastening fastening objects. <P>SOLUTION: This tapping screw 10 is screwed in a prepared hole H arranged by mutually communicating a plurality of fastening objects W1 and W2, to fasten the fastening objects W1 and W2, and includes a base body part 12, a head part 14 having an engaging groove part 20, a screw part 22 and a tip part 16. The base body part 12 has a circular base body part 12a of a cross-sectional circular shape and a noncircular base body part 12b of a cross-sectional noncircular shape. The screw part 22 is composed of a circular screw part 22a of a cross-sectional circular shape arranged on a peripheral surface of the circular base body part 12a and a cross-sectional noncircular screw part 22b arranged on a peripheral surface of the noncircular base body part 12b. The tapping screw 10 simultaneously satisfies b<d, e<a and c=e, when assuming an inner diameter of the prepared hole H as (a), an outer diameter of the noncircular screw part as (b), a trough diameter of the noncircular screw part as (c), an outer diameter of the circular screw part as (d) and a trough diameter of the circular screw part as (e). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

この発明は、タッピンねじに関し、特に、たとえば複数の締結対象物の相互に予めあけられた下孔にねじ込まれ、複数の締結対象物を締結するのに好適な、タッピンねじに関する。 The present invention relates to a tapping screw, and more particularly, to a tapping screw that is suitable for fastening a plurality of fastening objects, for example, by screwing into a plurality of pre-opened holes of a plurality of fastening objects.

この発明の背景となる先行技術には、たとえば木製のパネル材（締結対象物）と金属製のパネル材（締結対象物）とを締結するのに用いられるタッピングねじがあった。このタッピングねじ１は、たとえば図９に示すように、ねじ部３と、ねじ部３の胴部（基体部）５ａに一体となった首部５ｂと、首部５ｂと一体となった頭部７とを有する。頭部７の上面は、平坦面７ａとなっており、頭部７の平坦面７ａには、電動ドリル等の回転工具が係合する係合穴９が設けられている。このタッピングねじ１を用いて、金属製のパネル材Ｗ１と木製のパネル材Ｗ２とを締結するには、たとえば図１０に示すように、金属製のパネル材Ｗ１の上に木製のパネル材Ｗ２を配置した状態で、電動ドリル等を用いて木製のパネル材Ｗ２から金属製のパネル材Ｗ１まで貫通する下孔Ｈが設けられ、その後、下孔Ｈにタッピングねじ１がねじ込まれることによって、木製のパネル材Ｗ１と金属製のパネル材Ｗ２とが締結される。この場合、下孔Ｈの内周面には、タッピングねじ１により、ねじ面を有するねじ孔が形成されるものとなる。 In the prior art as the background of the present invention, for example, there is a tapping screw used to fasten a wooden panel material (fastening object) and a metal panel material (fastening object). For example, as shown in FIG. 9, the tapping screw 1 includes a screw part 3, a neck part 5b integrated with a body part (base part) 5a of the screw part 3, and a head part 7 integrated with the neck part 5b. Have The upper surface of the head 7 is a flat surface 7a, and the flat surface 7a of the head 7 is provided with an engagement hole 9 for engaging a rotary tool such as an electric drill. In order to fasten the metal panel member W1 and the wooden panel member W2 using the tapping screw 1, for example, as shown in FIG. 10, the wooden panel member W2 is placed on the metal panel member W1. In the arranged state, a pilot hole H that penetrates from the wooden panel material W2 to the metal panel material W1 using an electric drill or the like is provided, and then the tapping screw 1 is screwed into the lower hole H, thereby The panel material W1 and the metal panel material W2 are fastened. In this case, a screw hole having a thread surface is formed on the inner peripheral surface of the lower hole H by the tapping screw 1.

また、この発明の背景となる他の先行技術には、貨物自動車の荷台の床構造に用いられて、特に、荷台を構成する複数本の金属製の根太材と、根太材の上に配置される木製の床板とを締結する場合に用いられるタッピングねじがあった（例えば、特許文献１参照）。このタッピングねじは、頭部の背面側にテーパ面を有し、木製の床板を金属製の根太材にねじ止めする際に、床板の一部を塑性変形させる木材押し付け面が設けられている。さらに、木材押し付け面には、切り込み突起が設けられている。
このタッピングねじを用いて根太材と床板とを締結する場合、先ず、床板および根太材にそれらを貫通する下孔が設けられ、次に、その下孔にタッピングねじがねじ込まれることによって、床板と根太材とが締結される。この場合、該タッピングねじのテーパ面により押し広げられるように塑性変形する床板の一部をそのままタッピングねじの径方向外方に向かわせることなく、タッピングねじの回転方向に移動させて、木材押し付け面内に取り込んで捕捉することができる。そのため、この荷台の床構造では、床板の表面にタッピングねじの頭部の外周から木材のバリが突出することがなくなるので、ねじ止め後のバリ取り作業を不要とすることができる。 In addition, another prior art as the background of the present invention is used for a floor structure of a loading platform of a truck, and in particular, a plurality of metal joists constituting the loading platform and disposed on the joists. There has been a tapping screw used for fastening a wooden floor board (see, for example, Patent Document 1). This tapping screw has a tapered surface on the back side of the head, and is provided with a wood pressing surface that plastically deforms a part of the floor board when the wooden floor board is screwed to a metal joist. Furthermore, the lug protrusion is provided in the wood pressing surface.
When fastening the joists and floorboards using this tapping screw, first, the floorboard and joists are provided with pilot holes that pass through them, and then the tapping screws are screwed into the lower holes, thereby The joist is fastened. In this case, the wood pressing surface is moved in the rotation direction of the tapping screw without directing a part of the floor plate that is plastically deformed so as to be spread by the taper surface of the tapping screw as it is directed outward in the radial direction of the tapping screw. Can be captured and captured inside. For this reason, in this floor structure of the loading platform, burrs of wood do not protrude from the outer periphery of the head of the tapping screw on the surface of the floor plate, so that deburring work after screwing can be eliminated.

特開２００５−２７１６１２号公報（第４頁−第５頁、図３−図５）Japanese Patent Laying-Open No. 2005-271612 (pages 4 to 5, FIGS. 3 to 5)

しかしながら、図９に示すタッピングねじ１を用いて、金属製のパネル材Ｗ１と木製のパネル材Ｗ２とを締結した場合、図１０に示すように、下孔Ｈにねじ込まれたタッピングねじ１は、木製のパネル材Ｗ２および金属製のパネル材Ｗ１に貫通されて外部に突出するように設置される。この場合、図９に示す従来のタッピングねじ１では、頭部７の下部にある首部５ｂおよび胴部（基体部）５ａの太さが、略一定の太さになるように形成され、さらに、ねじ部３の外径が上から下まで一定とされているので、当該タッピングねじ１の突出部分と金属製のパネル材Ｗ１および木製のパネル材Ｗ２の下孔Ｈに設けられたねじ孔との間に隙間Ｃが形成される。そのため、このタッピングねじ１で締結された締結対象物（金属製のパネル材Ｗ１および木製のパネル材Ｗ２）が、家屋の台所、洗面所、トイレ等の水を扱う箇所、所謂、水廻りに使用される場合で、特に、金属製のパネル材Ｗ１の下面側が外部に露出している場合には、当該隙間Ｃから水が浸入する恐れがあった。この場合、当該隙間Ｃから浸入した水によって、木製のパネル材Ｗ２が腐ってタッピングねじ１の締結力が弱いものとなり、遂には、タッピングねじ１が外れてしまう恐れがあった。また、当該隙間Ｃから浸入した水が、木製のパネル材Ｗ２の表面側に漏れ出る水上がり現象が起こり、それによる種々の不具合も生じる恐れがあった。 However, when the metal panel member W1 and the wooden panel member W2 are fastened using the tapping screw 1 shown in FIG. 9, the tapping screw 1 screwed into the pilot hole H as shown in FIG. It is installed so as to penetrate the wooden panel material W2 and the metal panel material W1 and to protrude outside. In this case, in the conventional tapping screw 1 shown in FIG. 9, the thickness of the neck portion 5b and the trunk portion (base portion) 5a at the lower portion of the head portion 7 is formed to be substantially constant, Since the outer diameter of the screw portion 3 is constant from the top to the bottom, the protruding portion of the tapping screw 1 and the screw holes provided in the lower holes H of the metal panel material W1 and the wooden panel material W2 A gap C is formed between them. Therefore, the objects to be fastened (the metal panel material W1 and the wooden panel material W2) fastened with the tapping screw 1 are used in places where water is handled such as kitchens, washrooms, toilets, etc., in the so-called water environment. In particular, when the lower surface side of the metal panel material W1 is exposed to the outside, there is a risk that water may enter from the gap C. In this case, the water that has entered from the gap C may cause the wooden panel material W2 to rot and weaken the fastening force of the tapping screw 1 and eventually cause the tapping screw 1 to come off. Moreover, the water rising phenomenon which the water which permeated from the said clearance gap C leaks to the surface side of the wooden panel material W2 occurred, and there also existed a possibility that various malfunctions by it might arise.

この点については、特許文献１に示す従来のタッピングねじも、図９および図１０に示すタッピングねじ１と同様である。すなわち、特許文献１に示されるタッピングねじによって締結された貨物自動車の荷台の床構造においても、タッピングねじの外径が上から下まで略同じ径に形成されていて、また、このタッピングねじは、通常、床板および根太材を貫通して外部に突出するように配設されている。この場合、床板および根太材を貫通する下孔に設けられたねじ孔と、タッピングねじの突出部分との間には、たとえば図５で示された隙間Ｃと同様の隙間が形成されるので、根太材の下面側から、水が浸入しやすくなっている。そのため、貨物自動車の荷台に載置された商品が濡れたり、床板自体が腐食したりする不具合が生じる恐れがあった。 In this regard, the conventional tapping screw shown in Patent Document 1 is the same as the tapping screw 1 shown in FIGS. That is, even in the floor structure of a cargo truck bed fastened by a tapping screw shown in Patent Document 1, the outer diameter of the tapping screw is formed to be substantially the same from top to bottom. Usually, it arrange | positions so that a floor board and a joist material may be protruded outside. In this case, for example, a gap similar to the gap C shown in FIG. 5 is formed between the screw hole provided in the lower hole penetrating the floor plate and the joist and the protruding portion of the tapping screw. Water easily enters from the lower surface side of the joist. For this reason, there is a risk that a product placed on the loading platform of the lorry gets wet or the floor board itself is corroded.

それゆえに、この発明の主たる目的は、締結対象物を締結した場合に、外部からの水の浸入を、特に、ねじ部の先端部側から頭部側への水の浸入を防止することができる、タッピンねじを提供することである。 Therefore, the main object of the present invention is to prevent the intrusion of water from the outside, particularly the intrusion of water from the tip side to the head side of the screw portion when the fastening object is fastened. To provide a tapping screw.

この発明にかかるタッピンねじは、複数の締結対象物の相互に連通して設けられた下孔にねじ込まれ、複数の締結対象物を締結する金属製のタッピンねじであって、タッピンねじは、軸状の基体部と、基体部の軸方向の一方側に配設される頭部と、頭部の上面に配設され、電動ドリル等の回転工具が係合可能となる係合溝部と、基体部に配設されるねじ部と、基体部の軸方向の他方側に配設される先端部とを含み、基体部は、基体部の軸方向の一端側から中間部にかけて配設された断面円形状の円形状基体部分と、基体部の軸方向の中間部から他端側にかけて配設された断面非円形状の非円形状基体部分とを含み、ねじ部は、円形状基体部分の周面に配設される断面円形状の円形状ねじ部と、非円形状基体部分の周面に配設される断面非円形状の非円形状ねじ部とを含み、下孔の径をａとし、非円形状ねじ部の外径をｂとし、非円形状ねじ部の谷径をｃとし、円形状ねじ部の外径をｄとし、円形状ねじ部の谷径をｅとした場合、ｂ＜ｄ，ｅ＜ａおよびｃ＝ｅを同時に満足して、下孔に当該タッピンねじがねじ込まれたとき、非円形状ねじ部で下孔に形成された雌ねじ部に、円形状ねじ部がねじ込まれることにより、雌ねじ部の谷部分が塑性変形されて雌ねじ部の谷部分と円形状ねじ部の谷部分とが密着することを特徴とする、タッピンねじである。
この発明にかかるタッピンねじでは、非円形状ねじ部が断面非円形状に形成されているので、下孔の内周面との接触部分が、断面円形状のものに比べて、ねじ込みに必要な推進力やねじ込み始動トルク（ねじ込みトルク）を小さくすることが可能となる。そのため、非円形状ねじ部によるタッピング抵抗は小さいものとなり、先行して下孔に設けられるねじ孔をスムーズに形成することができる。非円形状ねじ部は、後に続く円形状ねじ部によるねじ込み作用を案内する案内機能を有し、始動トルクの軽減を図るものとなっている。
この非円形状ねじ部が下孔にねじ込まれると、下孔にねじ孔（雌ねじ）が形成されることとなる。この場合、雌ねじの谷部分が塑性変形により盛り上がり、当該雌ねじの谷部分と非円形状ねじ部の谷部分とは、その間に僅かな隙間をもって接近するものとなる。
さらに、このタッピンねじでは、非円形状ねじ部のねじ込み作用に引き続いて、円形状ねじ部が下孔にねじ込まれる。円形状ねじ部は、先行する非円形状ねじ部により下孔に形成された雌ねじ部に、ねじ込まれる。この場合、ｂ＜ｄ，ｅ＜ａおよびｃ＝ｅを同時に満足しているので、下孔に形成された雌ねじ部に、さらに円形状ねじ部がねじ込まれることにより、雌ねじ部の谷部分が塑性変形されてさらに一層盛り上がり、雌ねじ部の谷部分と円形状ねじ部の谷部分とが密着するため、円形状ねじ部は雌ねじ部に強固にねじ込まれる。それゆえ、円形状ねじ部は、その谷の部分と下孔部分との間に隙間が無いように、下孔に喰い込んだ状態となる。
このことを言い換えると、タッピンねじは、複数の締結対象物の相互に設けられた下孔を介して、当該締結対象物に「はめ殺し」の状態となるようにねじ込まれる。したがって、この発明にかかるタッピンねじにより複数の締結対象物を締結した場合、たとえば図５に示した従来のタッピングねじ１および特許文献１で示したタッピングねじにより複数の締結対象物を締結した場合に比べて、特に、円形状ねじ部の谷の部分と下孔の内周面との間の隙間Ｃが閉塞されるため、ねじ込まれたねじ部の先端部側から頭部のねじ込み側への水の浸入（水上がり）を防止することが可能となる。しかも、当該タッピンねじのねじ部の下孔に対するねじかかりが大きくなるので、緩み防止効果も向上するものとなる。
また、この発明にかかるタッピンねじにおいて、非円形状基体部および非円形状ねじ部は、断面多角形状に形成されることが好ましく、断面三角形状に形成されることがさらに好ましい。
この場合、非円形状基体部および非円形状ねじ部が断面多角形状に形成されると、下孔に対するタッピンねじのねじ込み開始時における始動トルク（ねじ込みトルク）をより小さくすることが可能となり、安定した非円形状ねじ部の案内機能を発揮させることができる。さらに、非円形状基体部および非円形状ねじ部が断面三角形状に形成されると、非円形状ねじ部のねじ込み開始時における始動トルク（ねじ込みトルク）をより一層小さくすることが可能となる。
一方、この発明にかかるタッピンねじを用いた締結対象物の締結構造は、複数の締結対象物が、木製の締結対象物と金属製の締結対象物とを含み、木製の締結対象物および金属製の締結対象物の相互に連通して設けられた下孔を有し、当該下孔に木製の締結対象物の表面側から、上述した発明にかかるタッピンねじがねじ込まれることにより、木製の締結対象物と金属製の締結対象物とが締結されることを特徴とする、タッピンねじを用いた締結対象物の締結構造である。
この発明にかかるタッピンねじを用いた締結対象物の締結構造では、上述した発明にかかるタッピンねじにより、ねじ込まれたねじ部の先端部側から頭部のねじ込み側への水の浸入（水上がり）を防止することが可能となるため、金属製の締結対象物の上面に木製の締結対象物が配置され、木製の締結対象物の上面側から当該タッピンねじで締結した場合、木製の締結対象物への水の浸入（水上がり）および木製の締結対象物の上面側への水の浸入（水上がり）を防止することができる。 A tapping screw according to the present invention is a metal tapping screw that is screwed into a pilot hole provided in communication with each other of a plurality of fastening objects and fastens the plurality of fastening objects. A base portion, a head portion disposed on one side of the base portion in the axial direction, an engagement groove portion disposed on an upper surface of the head portion and capable of engaging with a rotary tool such as an electric drill, and a base portion A cross section disposed from one end side of the base portion in the axial direction to the middle portion thereof, including a screw portion disposed in the base portion and a tip portion disposed on the other side in the axial direction of the base portion. A circular circular base portion, and a non-circular base portion having a non-circular cross-section disposed from the intermediate portion in the axial direction of the base portion to the other end side, and the screw portion is a circumference of the circular base portion. A circular thread portion with a circular cross section disposed on the surface and a non-circular cross section disposed on the peripheral surface of the non-circular base portion The diameter of the pilot hole is a, the outer diameter of the non-circular thread portion is b, the valley diameter of the non-circular thread portion is c, and the outer diameter of the circular thread portion is where d is the valley diameter of the circular threaded portion, and e is the non-circular threaded portion satisfying b <d, e <a and c = e at the same time, and the tapping screw is screwed into the lower hole. When the circular screw portion is screwed into the female screw portion formed in the pilot hole, the valley portion of the female screw portion is plastically deformed so that the valley portion of the female screw portion and the valley portion of the circular screw portion are in close contact with each other. This is a tapping screw.
In the tapping screw according to the present invention, since the non-circular thread portion is formed in a non-circular cross section, the contact portion with the inner peripheral surface of the lower hole is necessary for screwing in comparison with a circular cross section. The propulsive force and the screwing start torque (screwing torque) can be reduced. Therefore, the tapping resistance due to the non-circular thread portion is small, and the screw hole provided in the lower hole in advance can be formed smoothly. The non-circular thread portion has a guide function for guiding the screwing action by the subsequent circular thread portion, and reduces the starting torque.
When this non-circular thread portion is screwed into the lower hole, a screw hole (female screw) is formed in the lower hole. In this case, the valley portion of the female screw rises due to plastic deformation, and the valley portion of the female screw and the valley portion of the non-circular screw portion approach each other with a slight gap therebetween.
Furthermore, in this tapping screw, following the screwing action of the non-circular threaded portion, the circular threaded portion is screwed into the prepared hole. The circular thread portion is screwed into the female thread portion formed in the prepared hole by the preceding non-circular thread portion. In this case, since b <d, e <a and c = e are satisfied at the same time, a circular screw portion is further screwed into the female screw portion formed in the prepared hole, so that the valley portion of the female screw portion is plastic. Since the deformation is further increased and the valley portion of the female screw portion and the valley portion of the circular screw portion are in close contact with each other, the circular screw portion is firmly screwed into the female screw portion. Therefore, the circular threaded portion is in a state of being bitten into the lower hole so that there is no gap between the valley portion and the lower hole portion.
In other words, the tapping screw is screwed into the fastening object so as to be in a “fitting-killing” state through the prepared holes of the plurality of fastening objects. Therefore, when a plurality of fastening objects are fastened by the tapping screw according to the present invention, for example, when a plurality of fastening objects are fastened by the conventional tapping screw 1 shown in FIG. 5 and the tapping screw shown in Patent Document 1. In comparison, in particular, the gap C between the valley portion of the circular screw portion and the inner peripheral surface of the lower hole is closed, so that the water from the tip portion side of the screwed screw portion to the screwing side of the head portion is reduced. It becomes possible to prevent the intrusion (water rising). In addition, since the threading of the tapping screw into the prepared hole of the threaded portion is increased, the effect of preventing loosening is also improved.
In the tapping screw according to the present invention, the non-circular base portion and the non-circular screw portion are preferably formed in a polygonal cross section, and more preferably in a triangular shape.
In this case, if the non-circular base portion and the non-circular thread portion are formed in a polygonal cross section, the starting torque (screwing torque) at the start of screwing of the tapping screw into the lower hole can be further reduced, and stable. The guiding function of the non-circular threaded portion can be exhibited. Furthermore, when the non-circular base portion and the non-circular screw portion are formed in a triangular cross section, the starting torque (screw-in torque) at the start of screwing of the non-circular screw portion can be further reduced.
On the other hand, in the fastening structure of the fastening object using the tapping screw according to the present invention, the plurality of fastening objects include a wooden fastening object and a metal fastening object, the wooden fastening object and the metal fastening object. The fastening object of the present invention has a pilot hole provided in communication with each other, and the wooden fastening object is screwed into the pilot hole from the surface side of the wooden fastening object by the tapping screw according to the invention described above. A fastening structure of a fastening object using a tapping screw, wherein an object and a metal fastening object are fastened.
In the fastening structure of the fastening object using the tapping screw according to the present invention, water enters from the tip end side of the screwed portion into the screwing side of the head (water rising) by the tapping screw according to the above-described invention. Therefore, when a wooden fastening object is arranged on the upper surface of a metal fastening object and fastened with the tapping screw from the upper surface side of the wooden fastening object, the wooden fastening object It is possible to prevent water from entering (water rising) and water from entering the upper surface side of the wooden fastening object (water rising).

この発明にかかるタッピンねじによれば、締結対象物を締結した場合に、外部からの水の浸入を、特に、ねじ部の先端部側から頭部側への水の浸入を防止することができる、という効果がある。 According to the tapping screw according to the present invention, when a fastening object is fastened, it is possible to prevent water from entering from the outside, in particular, water from the front end side to the head side of the screw portion. There is an effect that.

この発明の上述の目的、その他の目的、特徴および利点は、図面を参照して行う以下の発明を実施するための最良の形態の説明から一層明らかとなろう。 The above-mentioned object, other objects, features, and advantages of the present invention will become more apparent from the following description of the best mode for carrying out the invention with reference to the drawings.

この実施形態にかかるタッピンねじは、複数の締結対象物の相互に連通して設けられた下孔にねじ込まれて締結対象物を締結した場合に、外部からの水の浸入を、特に、頭部とは反対側のねじ込み先端部側から頭部のねじ込み側への水の浸入を防止するという目的を、断面円形状のねじ部および当該断面円形状の円形状ねじ部の外径よりも小さい外径を有する断面三角形状のねじ部を有する非円形状ねじ部を形成し、下孔の径をａとし、非円形状ねじ部の外径をｂとし、非円形状ねじ部の谷径をｃとし、円形状ねじ部の外径をｄとし、円形状ねじ部の谷径をｅとした場合、ｂ＜ｄ，ｅ＜ａおよびｃ＝ｅを同時に満足するように円形状ねじ部および非円形状ねじ部を形成することによって実現した。 The tapping screw according to this embodiment, when screwed into a pilot hole provided in communication with each other of a plurality of fastening objects to fasten the fastening object, in particular, intrusion of water from the outside, in particular, the head The purpose of preventing water from entering from the screw tip side opposite to the screw side to the screw side of the head is an outer diameter smaller than the outer diameter of the thread portion having a circular cross section and the circular thread portion having the circular cross section. A non-circular thread part having a triangular thread part having a diameter is formed, the diameter of the pilot hole is a, the outer diameter of the non-circular thread part is b, and the root diameter of the non-circular thread part is c When the outer diameter of the circular threaded portion is d and the valley diameter of the circular threaded portion is e, b <d, e <a and c = e are satisfied so that b <d, e <a and c = e are satisfied simultaneously. This was realized by forming a shape screw part.

図１は、この発明にかかるタッピンねじの実施形態の一例を示す図解図であって、（Ａ）はその正面図解図であり、（Ｂ）その底面図解図である。また、図２は、この発明にかかるタッピンねじを用いて複数の締結対象物を締結する前の状態を示す断面図解図であり、図３は、この発明にかかるタッピンねじを用いて複数の締結対象物を締結する途中の状態を示す断面図解図であり、図５は、この発明にかかるタッピンねじを用いて複数の締結対象物を締結した状態を示す断面図解図である。
本実施形態例では、たとえば貨物自動車の荷台の床構造に用いられて、特に、たとえば、図２〜図５に示すように、荷台本体を構成する複数本の金属製の根太材Ｗ２（締結対象物）と、根太材Ｗ２の上に配置された木製の床板Ｗ１（締結対象物）とを締結する場合に用いられ、特に、図２に示すように、床板Ｗ１および根太材Ｗ２の相互に連通して設けられた下孔Ｈにねじ込まれることによって、床板Ｗ１と根太材Ｗ２とを締結する金属製のタッピンねじ１０について、以下、説明する。 FIG. 1 is an illustrative view showing an example of an embodiment of a tapping screw according to the present invention, in which (A) is a front schematic view and (B) a bottom schematic view. 2 is a cross-sectional view illustrating a state before a plurality of fastening objects are fastened using the tapping screws according to the present invention, and FIG. 3 is a plurality of fastening states using the tapping screws according to the present invention. FIG. 5 is a cross-sectional view showing a state in the middle of fastening the object, and FIG. 5 is a cross-sectional view showing a state where a plurality of fastening objects are fastened using the tapping screw according to the present invention.
In the present embodiment, for example, it is used for a floor structure of a loading platform of a lorry, for example, as shown in FIGS. 2 to 5, for example, a plurality of metal joists W2 (fastening objects) constituting a loading platform main body. 2) and a wooden floor board W1 (fastening object) disposed on the joist member W2, particularly as shown in FIG. 2, the floor board W1 and the joist member W2 communicate with each other. The metal tapping screw 10 that fastens the floor board W1 and the joist W2 by being screwed into the prepared lower hole H will be described below.

このタッピンねじ１０は、たとえば断面円形の軸状の基体部１２を含む。基体部１２は、その軸方向の一方側に頭部１４を有し、その軸方向の他方側に先端部１６を有する。基体部１２と頭部１４との間には、基体部１２および頭部１４と連接される首下部１８が配設されている。基体部１２は、基体部１２の軸方向の一端側から中間部にかけて配設される断面円形状の円形状基体部分１２ａと、基体部１２の軸方向の中間部から他端側にかけて配設される断面非円形状の非円形状基体部分１２ｂとを有する。頭部１４の表面（上面）には、電動ドリル等の回転工具が係合可能となるプラス溝（＋），マイナス溝（−）等の係合溝部２０が配設されている。基体部１２，頭部１４，先端部１６および首下部１８は、たとえば快削鋼等の特殊用途鋼で一体的に形成されている。 The tapping screw 10 includes, for example, an axial base portion 12 having a circular cross section. The base portion 12 has a head portion 14 on one side in the axial direction, and a tip portion 16 on the other side in the axial direction. A neck lower portion 18 connected to the base portion 12 and the head portion 14 is disposed between the base portion 12 and the head portion 14. The base portion 12 is provided with a circular base portion 12a having a circular cross section disposed from one end side in the axial direction of the base portion 12 to the intermediate portion, and from the intermediate portion in the axial direction of the base portion 12 to the other end side. And a non-circular base portion 12b having a non-circular cross section. On the surface (upper surface) of the head 14, an engagement groove 20 such as a plus groove (+) and a minus groove (−) that can be engaged with a rotary tool such as an electric drill is disposed. The base portion 12, the head portion 14, the tip portion 16, and the neck lower portion 18 are integrally formed of special purpose steel such as free-cutting steel.

また、基体部１２には、その軸方向の一端側から他端側にかけて、ねじ部２２が形成されている。ねじ部２２は、基体部１２の周面に形成されている。ねじ部２２は、円形状基体部分１２ａの周面に配設される断面円形状の円形状ねじ部２２ａと、非円形状基体部分１２ｂの周面に配設される断面非円形状の非円形状ねじ部２２ｂとを含む。このタッピンねじ１０では、非円形状基体部分１２ｂおよび非円形状ねじ部２２ｂが、特に、図１（Ｂ）に示すように、たとえば３つの弧状部分２４ａ，２４ｂおよび２４ｃを有する断面三角形状に形成されている。３つの弧状部分２４ａ，２４ｂおよび２４ｃは、それぞれ、その中央部分にいくにしたがって次第に外側に膨出したものとなっている。この断面三角形状部分の３つの頂点部２６ａ，２６ｂおよび２６ｃに外接する円（図示せず）は、円形状ねじ部２２ａの外径よりも小さく形成されている。この断面三角形状部分は、ねじ部２２の先端部１６側部分において、僅かにテーパ状に形成されている。
なお、非円形状基体部分１２ｂおよび非円形状ねじ部２２ｂは、断面三角形状のもの以外に、たとえば断面四角形状、断面五角形状、断面六角形状、その他の断面多角形状に形成されたものも適宜用いられ得る。 Further, the base portion 12 is formed with a screw portion 22 from one end side in the axial direction to the other end side. The screw portion 22 is formed on the peripheral surface of the base portion 12. The screw portion 22 includes a circular screw portion 22a having a circular cross section disposed on the peripheral surface of the circular base portion 12a and a non-circular non-circular cross section disposed on the peripheral surface of the noncircular base portion 12b. Shape screw portion 22b. In this tapping screw 10, the non-circular base portion 12b and the non-circular screw portion 22b are formed in a triangular cross section having, for example, three arc-shaped portions 24a, 24b and 24c, as shown in FIG. Has been. Each of the three arc-shaped portions 24a, 24b, and 24c gradually bulges outward toward the central portion. A circle (not shown) circumscribing the three apex portions 26a, 26b, and 26c of the triangular section is formed smaller than the outer diameter of the circular screw portion 22a. The triangular section is formed in a slightly tapered shape at the tip 16 side portion of the screw portion 22.
The non-circular base portion 12b and the non-circular threaded portion 22b may be appropriately formed, for example, in a cross-sectional square shape, a cross-sectional pentagonal shape, a cross-sectional hexagonal shape, or other polygonal cross-sectional shapes in addition to the triangular cross-sectional shape. Can be used.

このタッピンねじ１０では、たとえば図２に示すように、上記した下孔Ｈの内径をａとし、また、図１に示すように、非円形状ねじ部２２ｂの外径をｂとし、非円形状ねじ部２２ｂの谷径をｃとし、円形状ねじ部２２ａの外径をｄとし、円形状ねじ部２２ａの谷径をｅとした場合、ｂ＜ｄ，ｅ＜ａおよびｃ＝ｅを同時に満足するように、タッピンねじ１０が形成されている。 In this tapping screw 10, for example, as shown in FIG. 2, the inner diameter of the prepared hole H is a, and as shown in FIG. 1, the outer diameter of the non-circular screw portion 22 b is b, and the non-circular shape is formed. When the valley diameter of the screw portion 22b is c, the outer diameter of the circular screw portion 22a is d, and the valley diameter of the circular screw portion 22a is e, b <d, e <a and c = e are satisfied simultaneously. As shown, a tapping screw 10 is formed.

このタッピンねじ１０を用いて、木製の床板Ｗ１と金属製の根太材Ｗ２とを締結する場合には、たとえば図２に示すように、金属製の根太材Ｗ２の上面に木製の床板Ｗ１を載置した状態で、電動ドリル等を用いて木製の床板Ｗ１から金属製の根太材Ｗ２まで貫通する下孔Ｈが設けられた後、たとえば図３および図５に示すように、下孔Ｈにタッピンねじ１０がねじ込まれる。それによって、木製の床板Ｗ１と金属製の根太材Ｗ２とが締結される。 When the wooden floor board W1 and the metal joist member W2 are fastened using the tapping screw 10, for example, as shown in FIG. 2, the wooden floor board W1 is placed on the upper surface of the metal joist member W2. After the pilot hole H penetrating from the wooden floor board W1 to the metal joist W2 is provided using an electric drill or the like, the tap hole is tapped as shown in FIGS. 3 and 5, for example. Screw 10 is screwed. Thereby, the wooden floor board W1 and the metal joist W2 are fastened.

この場合、タッピンねじ１０は、非円形状ねじ部２２ｂが断面三角形状に形成されているため、非円形状ねじ部２２ｂによるタッピング抵抗が小さいものとなり、先行するねじ孔を下孔Ｈにスムーズに形成することができる。このタッピンねじ１０では、下孔Ｈの内周面との接触部分が、断面円形状のものに比べて少なく、ねじ込みに必要な推進力やねじ込み始動トルク（ねじ込みトルク）を小さくすることができるため、非円形状ねじ部２２ｂによって、下孔Ｈにスムーズに先行するねじ孔Ｈｓ（以下、雌ねじ部Ｈｓという。）を形成することができる。つまり、非円形状ねじ部２２ｂは、タッピンねじのねじ込み開始時において、後に続く円形状ねじ部２２ａによるねじ込み作用を案内する案内機能と共に、始動トルクを軽減する機能を有するものとなっている。
この非円形状ねじ部２２ｂが下孔Ｈにねじ込まれると、下孔Ｈに雌ねじ部Ｈｓが形成されることとなる。この場合、雌ねじ部Ｈｓの谷部分が塑性変形により盛り上がり、当該雌ねじ部Ｈｓの谷部分と非円形状ねじ部２２ｂの谷部分とは、その間に僅かな隙間をもって接近するものとなる。
なお、図３では、締結対象物Ｗ（木製の床板Ｗ１および金属製の根太材Ｗ２）を締結する途中の状態を示す断面図解図であって、非円形状ねじ部２２ｂの先端部１６側が下孔Ｈから突出し、円形状ねじ部２２ａの少なくとも一部が金属製の根太材Ｗ２の厚み方向の中間部に位置するように、タッピンねじ１０が下孔Ｈにねじ込まれた状態を示している。 In this case, since the non-circular thread portion 22b is formed in a triangular cross section, the tapping screw 10 has a small tapping resistance due to the non-circular thread portion 22b, and the preceding screw hole is smoothly formed into the pilot hole H. Can be formed. In this tapping screw 10, the contact portion with the inner peripheral surface of the lower hole H is smaller than that of the circular cross section, and the driving force required for screwing and the screwing starting torque (screwing torque) can be reduced. The non-circular threaded portion 22b can form a threaded hole Hs (hereinafter referred to as a female threaded portion Hs) that smoothly precedes the lower hole H. That is, the non-circular thread portion 22b has a function of reducing the starting torque as well as a guide function for guiding the screwing action by the subsequent circular thread portion 22a at the start of screwing of the tapping screw.
When the non-circular threaded portion 22b is screwed into the lower hole H, the female threaded portion Hs is formed in the lower hole H. In this case, the valley portion of the female screw portion Hs rises due to plastic deformation, and the valley portion of the female screw portion Hs and the valley portion of the non-circular screw portion 22b approach each other with a slight gap.
In addition, in FIG. 3, it is sectional drawing solution figure which shows the state in the middle of fastening the fastening target object W (wood floor board W1 and metal joist W2), Comprising: The front-end | tip part 16 side of the non-circular thread part 22b is down The state where the tapping screw 10 is screwed into the lower hole H is shown so that it protrudes from the hole H and at least a part of the circular screw part 22a is located in the middle part in the thickness direction of the metal joist W2.

さらに、非円形状ねじ部２２ｂのねじ込み作用に引き続き、円形状ねじ部２２ａは、たとえば図３〜図５に示すように、先行する非円形状ねじ部２２ｂによって下孔Ｈに形成された雌ねじ部Ｈｓに、ねじ込まれる。図５では、円形状ねじ部２２ａの軸方向の中間部が雌ねじ部Ｈｓから突出するように、タッピンねじ１０が下孔Ｈにねじ込まれた状態を示している。
このタッピンねじ１０では、ｂ＜ｄ，ｅ＜ａおよびｃ＝ｅを同時に満足しているので、下孔Ｈに形成された雌ねじ部Ｈｓに、さらに円形状ねじ部２２ａがねじ込まれることにより、雌ねじ部Ｈｓの谷部分が塑性変形されてさらに一層盛り上がり、雌ねじ部Ｈｓの谷部分と円形状ねじ部２２ａの谷部分とが密着するため、円形状ねじ部２２ａは雌ねじ部Ｈｓに強固にねじ込まれる。それゆえ、円形状ねじ部２２ａは、その谷の部分と雌ねじ部Ｈｓの谷部分との間に隙間が無いように、下孔Ｈに喰い込んだ状態となる。
すなわち、このタッピンねじ１０は、金属製の根太材Ｗ２およびその上面に積層された木製の床板Ｗ１に、下孔Ｈを介して、「はめ殺し」の状態となるようにねじ込まれる。そのため、タッピンねじ１０は、たとえば図５に示すように、その円形状ねじ部２２ａが、木製の床板Ｗ１および金属製の根太材Ｗ２に対して、その保持力が大きいものとなっている。 Further, following the screwing action of the non-circular threaded portion 22b, the circular threaded portion 22a is a female threaded portion formed in the pilot hole H by the preceding noncircular threaded portion 22b as shown in FIGS. Screwed into Hs. FIG. 5 shows a state in which the tapping screw 10 is screwed into the lower hole H so that the axial middle portion of the circular screw portion 22a protrudes from the female screw portion Hs.
In this tapping screw 10, b <d, e <a and c = e are satisfied at the same time. Therefore, when the circular screw portion 22 a is further screwed into the female screw portion Hs formed in the pilot hole H, the female screw Since the valley portion of the portion Hs is further plastically deformed and further rises and the valley portion of the female screw portion Hs and the valley portion of the circular screw portion 22a are in close contact with each other, the circular screw portion 22a is firmly screwed into the female screw portion Hs. Therefore, the circular threaded portion 22a is in a state of biting into the lower hole H so that there is no gap between the valley portion and the valley portion of the female threaded portion Hs.
In other words, the tapping screw 10 is screwed into the metal joist W2 and the wooden floor board W1 laminated on the upper surface thereof through the pilot hole H so as to be in a “fitting kill” state. Therefore, as shown in FIG. 5, for example, the tapping screw 10 has a circular threaded portion 22a that has a large holding force with respect to the wooden floor board W1 and the metal joist W2.

したがって、このタッピンねじ１０によって、木製の床板Ｗ１と金属製の根太材Ｗ２とを締結した場合、たとえば図９に示した従来のタッピングねじおよび特許文献１で示したタッピングねじで複数の締結対象物を締結した場合に比べて、特に、円形状ねじ部２２ａの谷の部分と下孔Ｈに設けられた雌ねじ部Ｈｓの内周面との間の隙間Ｃを閉塞することができるため、このタッピンねじ１０では、当該タッピンねじ１０の先端部１６側から、頭部１４のねじ込み側への水の浸入（水上がり）を防止することができ、床板Ｗ１の上面側への水の浸入（水上がり）も防止することができる。そのため、貨物自動車の荷台に載置された商品が濡れたり、床板自体が腐食したりすることを防止することができる。しかも、当該タッピンねじのねじ部の下孔に対するねじかかりが大きくなるので、緩み防止効果も向上させることができる。 Therefore, when the wooden floor board W1 and the metal joist W2 are fastened by the tapping screw 10, a plurality of fastening objects are formed by, for example, the conventional tapping screw shown in FIG. 9 and the tapping screw shown in Patent Document 1. Since the gap C between the valley portion of the circular screw portion 22a and the inner peripheral surface of the female screw portion Hs provided in the lower hole H can be closed, compared with the case where the screw is fastened. In the screw 10, it is possible to prevent water from entering (water rising) from the tip 16 side of the tapping screw 10 to the screwing side of the head 14, and water intrusion (water rising) to the upper surface side of the floor board W <b> 1. ) Can also be prevented. Therefore, it is possible to prevent the product placed on the loading platform of the lorry from getting wet or corroding the floor board itself. In addition, since the screwing of the tapping screw into the prepared hole of the threaded portion is increased, the effect of preventing loosening can be improved.

本実施形態例にかかるタッピンねじ１０によって、木製の床板Ｗ１と金属製の根太材Ｗ２とを締結する場合、図５に示すように、ねじ部２２の円形状ねじ部２２ａが下孔Ｈに設けられた雌ねじ部Ｈｓから突出するようにタッピンねじ１０をねじ込むことが好ましいが、それに限定されるものではなく、たとえば図３に示すように、当該円形状ねじ部２２ａの少なくとも一部が金属製の根太材Ｗ２の厚み方向の中間部に位置するように、タッピンねじ１０を下孔Ｈに設けられた雌ねじ部Ｈｓにねじ込むようにしてもよい。 When the wooden floor board W1 and the metal joist W2 are fastened by the tapping screw 10 according to the present embodiment, a circular screw portion 22a of the screw portion 22 is provided in the lower hole H as shown in FIG. The tapping screw 10 is preferably screwed so as to protrude from the formed female screw portion Hs. However, the present invention is not limited to this, and for example, as shown in FIG. 3, at least a part of the circular screw portion 22a is made of metal. The tapping screw 10 may be screwed into the female screw portion Hs provided in the lower hole H so as to be positioned at the middle portion in the thickness direction of the joist W2.

なお、本実施形態例にかかるタッピンねじ１０では、非円形状ねじ部２２ｂの先端側の外径を下孔Ｈの内径ａよりも小さく形成することも可能であるが、非円形状ねじ部２２ｂの先端側の外径は、下孔Ｈの内径ａと略同じかそれよりも大きく形成されていることが好ましいものである。 In the tapping screw 10 according to the present embodiment, the outer diameter on the tip side of the non-circular thread portion 22b can be formed smaller than the inner diameter a of the lower hole H, but the non-circular thread portion 22b. It is preferable that the outer diameter on the front end side is substantially the same as or larger than the inner diameter a of the lower hole H.

図６は、この発明にかかるタッピンねじの実施形態の他の例を示す図解図であって、（Ａ）はその正面図解図であり、（Ｂ）その平面図解図であり、（Ｃ）は（Ａ）の線Ｙ−Ｙの断面図解図であり、（Ｄ）は（Ａ）の線Ｚ−Ｚの断面図解図である。さらに、図７の（Ａ）は、図６の（Ａ）の頭部および首部の要部拡大図であり、図６の（Ａ）の底面図解図である。
図６および図７に示す実施形態例は、上述した実施形態例と比べて、特に、バリ取り部３０およびツイスト部４０を有する点で相違する。すなわち、図６，図７の実施形態例のタッピンねじ１０は、バリ取り部３０を含む。バリ取り部３０は、頭部１４の下面に設けられたリング状の溝面３２を有する。溝面３２の内周縁側から首下部１８の根元側にかけては、たとえば正面視四角形状の１２個のリブ刃３４が放射線状に配設されている。１２個のリブ刃３４は、その刃先部分が、頭部１４の上面から見て、タッピンねじの回転方向（本実施形態例では、右ねじ方向）に対応するように形成されている。放射状に配列された１２個のリブ刃３４は、図５に示したようなバリ防止用の皿穴Ｈｃを切削するための切削刃としての機能を有すると共に、皿穴Ｈｃ内に頭部１４を沈み込ませるときの抵抗を小さくする機能を有する。 FIG. 6 is an illustrative view showing another example of an embodiment of a tapping screw according to the present invention, in which (A) is a front illustrative view thereof, (B) a plan illustrative view thereof, and (C) is represented. (A) It is a cross-sectional solution figure of line YY of (A), (D) is a cross-sectional solution figure of line ZZ of (A). 7A is an enlarged view of the main part of the head and neck of FIG. 6A, and is a bottom view solution view of FIG. 6A.
The embodiment shown in FIGS. 6 and 7 differs from the embodiment described above in that it has a deburring portion 30 and a twist portion 40 in particular. That is, the tapping screw 10 in the embodiment shown in FIGS. 6 and 7 includes a deburring portion 30. The deburring part 30 has a ring-shaped groove surface 32 provided on the lower surface of the head 14. From the inner peripheral edge side of the groove surface 32 to the base side of the neck lower part 18, for example, twelve rib blades 34 having a square shape in front view are arranged radially. The twelve rib blades 34 are formed so that the blade tip portions thereof correspond to the rotation direction of the tapping screw (in the present embodiment, the right screw direction) when viewed from the upper surface of the head 14. The twelve rib blades 34 arranged radially have a function as a cutting blade for cutting the countersink Hc for burr prevention as shown in FIG. 5, and the head 14 is placed in the countersink Hc. It has a function of reducing resistance when submerged.

また、溝面３２の外周縁側には、１２個のリブ刃３４と所定の間隔を隔てて、たとえば略弓形三角形の１２個のリブアーチ片３６が配設されている。１２個のリブアーチ片３６は、頭部１４の上面から見て、タッピンねじの回転方向（本実施形態例では、右ねじ方向）に向いた部分から反対側に漸次その高さが低くなるように所定の角度で傾斜して形成されている。これらのリブアーチ片３６は、上述したリブ刃３４と同様に、皿穴Ｈｃ内に頭部１４を沈み込ませるときの抵抗をより一層小さくする機能を有すると共に、バリ防止用の皿穴Ｈｃの内周壁面側とリブ刃３４との間に、バリ防止用の皿穴Ｈｃを切削したときの切り屑を把持する機能も有している。
なお、この実施形態例では、たとえば図７に示すように、頭部１４の下端周縁から溝面３２の底までの深さをＤ１とし、頭部１４の下端周縁からリブアーチ片３６の最も低い部分までの深さをＤ２としたとき、Ｄ２＜Ｄ１となるように設定されている。 Further, on the outer peripheral edge side of the groove surface 32, for example, 12 rib arch pieces 36 each having a substantially arcuate triangle shape are disposed at a predetermined interval from the 12 rib blades 34. The twelve rib arch pieces 36 are gradually lowered in height from the portion facing the rotation direction of the tapping screw (right screw direction in this embodiment) as viewed from the upper surface of the head 14. It is inclined at a predetermined angle. These rib arch pieces 36 have a function of further reducing the resistance when the head 14 is submerged in the countersink Hc, as in the case of the rib blade 34 described above, and the inside of the countersink hole Hc for preventing burr. Between the peripheral wall surface side and the rib blade 34, it also has a function of gripping chips when the countersink hole Hc for preventing burr is cut.
In this embodiment, for example, as shown in FIG. 7, the depth from the lower end periphery of the head 14 to the bottom of the groove surface 32 is D1, and the lowest portion of the rib arch piece 36 from the lower end periphery of the head 14 Is set so that D2 <D1.

図６，図７の実施形態例では、バリ防止用の皿穴Ｈｃの内周壁面側とリブ刃３４との間に、バリ防止用の皿穴Ｈｃを切削したときの切り屑を収容・保持することができる。この場合、リブ刃３４とリブアーチ片３６との間で、バリ防止用の皿穴Ｈｃを切削した際の切り屑の殆どが保持され、残りの切り屑（残渣）は、リブアーチ片３６と頭部１４の下端周縁との隙間３８から、その外側に排出される。 In the embodiment of FIGS. 6 and 7, chips are stored and retained when the countersink hole Hc for burr prevention is cut between the inner peripheral wall surface of the countersink hole Hc for burr prevention and the rib blade 34. can do. In this case, most of the chips when the countersink hole Hc for preventing burr is cut is held between the rib blade 34 and the rib arch piece 36, and the remaining chips (residues) are separated from the rib arch piece 36 and the head. 14 is discharged to the outside through a gap 38 between the peripheral edge of the lower end of 14.

さらに、このタッピンねじ１０は、ツイスト部４０を含む。ツイスト部４０は、タッピンねじ１０の軸方向で見て、首下部１８と円形状ねじ部２２ａとの間に配設され、円形状ねじ部２２ａの外径よりも大きい外径を有するものである。そのため、ツイスト部４０は、該ツイスト部４０と円形状ねじ部２２ａとの境界部に、段差部４２を有するものとなっている。また、ツイスト部４０のその外周面には、図６の（Ａ）に示すように、たとえば切刃がねじれドリルのようになったねじれ刃リーマ状部４４が配設されている。 Further, the tapping screw 10 includes a twist portion 40. The twist portion 40 is disposed between the neck lower portion 18 and the circular screw portion 22a when viewed in the axial direction of the tapping screw 10, and has an outer diameter larger than the outer diameter of the circular screw portion 22a. . Therefore, the twist part 40 has the level | step-difference part 42 in the boundary part of this twist part 40 and the circular shaped thread part 22a. Further, as shown in FIG. 6A, for example, a twisted blade reamer-like portion 44 whose cutting blade is like a twist drill is disposed on the outer peripheral surface of the twist portion 40.

このツイスト部４０は、当該タッピンねじ１０で締結対象物Ｗを締結した場合に、ツイスト部４０と円形状ねじ部２２ａとの境界の段差部４２によって、当該タッピンねじ１０のねじ込み深さを規定し安定させるための機能を有している。すなわち、ツイスト部４０から下のねじ部２２の先端側が締結対象物Ｗから突き抜けないようにするために、締結対象物Ｗの厚みに応じて、ツイスト部４０およびねじ部２２の軸方向の長さを適宜設定することができる。ツイスト部４０を有するタッピンねじ１０は、締結対象物Ｗがたとえば合板ないし耐力のない中間層を含む場合に好適なものとなる。
なお、ツイスト部４０は、たとえば図８に示すように、刃溝がねじれていない直刃リーマ状部４６を有するものであってもよい。 When the fastening object W is fastened with the tapping screw 10, the twisted portion 40 defines the screwing depth of the tapping screw 10 by the step portion 42 at the boundary between the twisting portion 40 and the circular screw portion 22 a. Has a function to stabilize. That is, in order to prevent the tip end side of the screw part 22 below the twist part 40 from penetrating from the fastening object W, the lengths of the twist part 40 and the screw part 22 in the axial direction according to the thickness of the fastening object W. Can be set as appropriate. The tapping screw 10 having the twist portion 40 is suitable when the fastening object W includes, for example, a plywood or an intermediate layer having no yield strength.
In addition, the twist part 40 may have the straight blade reamer-like part 46 in which the blade groove is not twisted, for example, as shown in FIG.

この発明にかかるタッピンねじは、特に、トラックおよびコンテナ車両等の貨物輸送用車両で囲いのある荷物収容室（荷台）の床構造において、金属製の根太材および根太材の上に配置された木製の床板材の相互に設けられた下孔にねじ込まれ、当該床板材および根太材を締結するという用途、あるいは、屋内外の水廻りに配置される構造物の外板等に用いられる複数のパネル材で形成された積層体において、該積層体に設けられた下孔にねじ込まれ、金属製のパネル材および木製のパネル材を締結するという用途に適用して好適なものである。 The tapping screw according to the present invention is a wooden joist member and a wooden member disposed on the joist member in a floor structure of a luggage storage room (loading platform) surrounded by a cargo transport vehicle such as a truck and a container vehicle. A plurality of panels that are screwed into the prepared holes in the floor board material and used to fasten the floor board material and joist, or the outer panel of a structure placed around the water indoors and outdoors In the laminated body formed with the material, it is suitable to be applied to the use of being screwed into the prepared hole provided in the laminated body and fastening the metal panel material and the wooden panel material.

この発明にかかるタッピンねじの実施形態の一例を示す図解図であって、（Ａ）はその正面図解図であり、（Ｂ）その底面図解図である。It is an illustration figure which shows an example of embodiment of the tapping screw concerning this invention, Comprising: (A) is the front view solution figure, (B) It is the bottom view solution figure. この発明にかかるタッピンねじを用いて複数の締結対象物を締結する前の状態を示す断面図解図である。It is a cross-sectional view solution figure which shows the state before fastening a some fastening target object using the tapping screw concerning this invention. この発明にかかるタッピンねじを用いて複数の締結対象物を締結する途中の状態を示す断面図解図である。It is a cross-sectional view solution figure which shows the state in the middle of fastening some fastening objects using the tapping screw concerning this invention. 図３のＸ部分の拡大図である。FIG. 4 is an enlarged view of a portion X in FIG. 3. この発明にかかるタッピンねじを用いて複数の締結対象物を締結した状態を示す断面図解図である。It is a cross-sectional view solution figure which shows the state which fastened the several fastening target object using the tapping screw concerning this invention. この発明にかかるタッピンねじの実施形態の他の例を示す図解図であって、（Ａ）はその正面図解図であり、（Ｂ）その平面図解図であり、（Ｃ）は（Ａ）の線Ｙ−Ｙの断面図解図であり、（Ｄ）は（Ａ）の線Ｚ−Ｚの断面図解図である。It is an illustration figure which shows the other example of embodiment of the tapping screw concerning this invention, Comprising: (A) is the front view solution figure, (B) The plan view solution figure, (C) is (A). It is a cross-sectional illustration of line YY, (D) is a cross-sectional illustration of line ZZ of (A). （Ａ）は、図６の（Ａ）の頭部および首部の要部拡大図であり、（Ｂ）は図６の（Ａ）の底面図解図である。(A) is the principal part enlarged view of the head and neck part of (A) of FIG. 6, (B) is a bottom view solution figure of (A) of FIG. この発明にかかるタッピンねじの実施形態の他の例を示す図解図であって、（Ａ）はその正面図解図であり、（Ｂ）その平面図解図である。It is an illustration figure which shows the other example of embodiment of the tapping screw concerning this invention, Comprising: (A) is the front view solution figure, (B) The plan view solution figure. この発明の背景となる従来のタッピンねじの一例を示す図解図であって、（Ａ）はその正面図解図であり、（Ｂ）その底面図解図である。It is an illustration figure which shows an example of the conventional tapping screw used as the background of this invention, Comprising: (A) is the front view solution figure, (B) It is the bottom view solution figure. 図９に示す従来のタッピンねじを用いて複数の締結対象物を締結した状態を示す断面図解図である。FIG. 10 is a cross-sectional view showing a state where a plurality of fastening objects are fastened using the conventional tapping screw shown in FIG. 9.

Explanation of symbols

１０タッピンねじ
１２基体部
１２ａ円形状基体部分
１２ｂ非円形状基体部分
１４頭部
１６先端部
１８首下部
２０係合溝部
２２ねじ部
２２ａ円形状ねじ部
２２ｂ非円形状ねじ部
２４ａ，２４ｂ，２４ｃ弧状部分
２６ａ，２６ｂ，２６ｃ断面三角形状部分の頂点部
Ｗ締結対象物
Ｗ１木製の床板
Ｗ２金属製の根太材
Ｈ下孔
Ｈｓ下孔に形成された雌ねじ部
ａ締結対象物に設けられた下孔の内径
ｂ非円形状ねじ部の外径
ｃ非円形状ねじ部の谷径
ｄ円形状ねじ部の外径
ｅ円形状ねじ部の谷径 DESCRIPTION OF SYMBOLS 10 Tapping screw 12 Base part 12a Circular base part 12b Non-circular base part 14 Head 16 Tip part 18 Neck lower part 20 Engaging groove part 22 Screw part 22a Circular thread part 22b Non-circular thread part 24a, 24b, 24c Arc shape Portions 26a, 26b, and 26c The apex portion of the triangular section W The object to be fastened W1 The wooden floor board W2 The metal joist H The lower hole Hs The female screw portion formed in the lower hole a The lower hole provided in the object to be fastened Inner Diameter b Outer Diameter of Non-Circular Threaded Part c Valley Diameter of Non-Circular Threaded Part d Outer Diameter of Circular Threaded Part e Valley Diameter of Circular Threaded Part

Claims

A metal tapping screw that is screwed into a pilot hole provided in communication with each other of a plurality of fastening objects, and fastens the plurality of fastening objects,
The tapping screw is disposed on an axial base portion, a head portion disposed on one side of the base portion in the axial direction, and an upper surface of the head portion, and can be engaged with a rotary tool such as an electric drill. An engaging groove portion, a screw portion disposed in the base portion, and a tip portion disposed on the other side in the axial direction of the base portion,
The base portion is provided with a circular base portion having a circular cross section disposed from one end side in the axial direction to the intermediate portion of the base portion, and from the intermediate portion in the axial direction of the base portion to the other end side. Including a non-circular base portion having a non-circular cross section,
The threaded portion includes a circular threaded portion having a circular cross section disposed on the peripheral surface of the circular base portion, and a noncircular shape having a noncircular cross section disposed on the peripheral surface of the noncircular base portion. Including a threaded portion,
The diameter of the lower hole is a, the outer diameter of the non-circular thread portion is b, the valley diameter of the non-circular thread portion is c, the outer diameter of the circular thread portion is d, and the circular shape If the root diameter of the thread portion is e, b <d, e <a and c = e are satisfied at the same time,
When the tapping screw is screwed into the pilot hole,
The trough portion of the female screw portion is plastically deformed by screwing the circular screw portion into the female screw portion formed in the pilot hole in the non-circular thread portion, and the trough portion of the female screw portion and the circular shape. A tapping screw, characterized in that the threaded portion is in close contact with the valley portion.

The non-circular base portion and the non-circular screw portion are formed in a triangular cross-section,
The diameter of the lower hole is a, the outer diameter of the non-circular thread portion is b, the valley diameter of the non-circular thread portion is c, the outer diameter of the circular thread portion is d, and the circular shape If the root diameter of the thread portion is e, b <d, e <a and c = e are satisfied at the same time,
When the tapping screw is screwed into the pilot hole,
The trough portion of the female screw portion is plastically deformed by screwing the circular screw portion into the female screw portion formed in the pilot hole in the non-circular thread portion, and the trough portion of the female screw portion and the circular shape. The tapping screw according to claim 1, wherein the thread portion is in close contact with a valley portion.

The plurality of fastening objects include a wooden fastening object and a metal fastening object, and have a pilot hole provided in communication with the wooden fastening object and the metal fastening object. Then, the wooden fastening object and the metal fastening object are formed by screwing the tapping screw according to claim 1 or 2 into the prepared hole from the surface side of the wooden fastening object. A fastening structure of a fastening object using a tapping screw, characterized in that the object is fastened.